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                                        <h1>Data Security </h1>
                                        <h2>When and why did he start to work on data security?</h2>
                                        Without precautions, communication networks are prone to malicious attack. Messages might be read by unauthorized person or altered, and even worse the original messages might be replaced by fraudulent messages.
                                        <p>Davies was aware of the need of data security and integrity while he was proposing for new method of data communication in the mid 60's:</p>
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                                            "the security of the information is a problem, however, which leads to a subject of research:Security of data in doing business via a national network. (This refers to security against unauthorized access rather than against loss of data.)"<span> -(ref. [1], Para. 6, Pg. 1)</span>
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                                            "For security, the system might provide from a third source to each end of a transmission path a one time pad on demand. This would ensure that nowhere in the network was the data in clear. There would, of course, be a limit to the degree of security that a public service could offer."<span> -(ref. [1],  Pg. 3)</span>
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                                            "It is also possible for the interface unit to route related messages by different paths,
                                            which may be important for cryptography or for security against breakdown."<span> -(ref[2], Pg. 12)</span>
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                        References.
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                            <li>[1] D W Davies, <a target="_new" href="../archives/Davies02.pdf">Remote on-line Data Processing and its Communication Needs</a></li>
                            <li>[2] D W Davies, <a target="_new" href="../archives/Davies04.pdf">Proposal for Digital Communication Network</a></li>
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